Processor circuits can include a large number of integrated transistors and other components interconnected on a common die (chip). A processor circuit can be mounted on a substrate to form a package, and the package can subsequently be mounted on a printed circuit board for installation in a larger electronic system. Modern processor circuits regularly integrate multiple different functions, such as graphics, display engines, security engines and others on a single chip. Processor circuit-based products can be complicated in design, and the same or similar processor circuits can be configured to service a variety of market segments, such as server, desktop, mobile, or embedded system markets. Some markets seek to use single chip system-on-chip (SoC) solutions that combine at least some of a processor core, platform controller hub (PCH), memory controller hub (MCH), input/output controller (ICH) and other segment-specific acceleration elements onto a single chip.
Package size requirements for processor circuits are continually driven down to accommodate ultra small, thin, and light form factors, such as can be required for mobile or other devices. However, functionality requirements for smaller packages increase in every generation with feature additions, such as integrated clocks, digital signal processors, and multiple input/output interfaces, among others. In an example, distinct features or functions can correspond to different power domains in an integrated circuit, such as having different noise sensitivities and power signal requirements.
Inductors are used in integrated circuit applications including filters, power supplies, and voltage regulators. An inductor generally comprises a conductor that is configured to store energy in a magnetic field adjacent to the conductor when a current passes through the conductor. A conductor comprising a portion of the inductor typically includes one or more turns that can concentrate a magnetic field, induced by a current flowing through the conductor, in an area near the conductor. In some examples, integrated inductors include spiral traces in conductive layers, such as in conductive semiconductor, package, or printed circuit board substrate layers, to form inductor turns.